Ink jet printers continue to be improved as the technology for making the printheads continues to advance. New techniques are constantly being developed to provide low cost, highly reliable printers which approach the speed and quality of laser printers. An added benefit of ink jet printers is that color images can be produced at a fraction of the cost of laser printers with as good or better print quality than laser printers. All of the foregoing benefits exhibited by ink jet printers have also increased the competitiveness of suppliers to provide comparable printers in a more cost efficient manner than their competitors.
One area of improvement in the printers is in the print engine or printhead itself. This seemingly simple device is a relatively complicated structure containing electrical circuits, fluid channels and a variety of intricate, diminutive parts assembled with precision to provide a powerful, yet versatile ink jet pen. The primary components of the ink jet printhead are a semiconductor chip or substrate, a nozzle plate and a flexible circuit attached to the substrate. The semiconductor substrate is typically made of silicon and contains various passivation layers, conductive metal layers, resistive layers, insulative layers and protective layers deposited on a device side thereof (e.g., the side configured to secure ink ejecting devices thereon such as resistors and nozzle plates). The semiconductor substrate may comprise one or more ink passageways or fluid channels having specific geometries to control the characteristics of fluid flow (e.g., ink) to the nozzle plate. More particularly, because different systems or fluids require different channel dimensions and delivery angles to properly deliver the ink to the nozzle plate, fluid channels having specific geometries in the semiconductor substrate are desirable. However, the multiple steps associated with forming such fluid channels create issues.
Accordingly, there continues to be a need for fluid channels with specific geometries and improved processes for making the same.